Vehicle transmission controller

ABSTRACT

A vehicle transmission controller controls switching of the gear position of a transmission. The controller has a shift lever and an actuator. The shift lever is manipulated to select a gear position of the transmission. The actuator actuates the transmission to switch the gear position in accordance with a manipulation of the manipulator. The actuator switches the transmission to the gear position selected by the manipulator. The actuator switches the transmission to a predetermined gear position from the gear position selected by the manipulator when the vehicle satisfies predetermined conditions.

BACKGROUND OF THE INVENTION

The present invention relates to a transmission controller thatelectrically switches the position of a vehicle transmission.

Japanese Unexamined Patent Publication Ser. No. 5-272633 discloses avehicle transmission controller. In this transmission controller, ashift controller controls a gear change actuator based on a manipulationof the shift lever of a shifting device including a park position (P), aneutral position (N), a drive position (D), and a reverse position (R).

To move a vehicle equipped with such a transmission controller from astandstill, a driver starts the engine while maintaining thetransmission in the park position or the neutral position and thenmanually moves the shift lever to switch the gear train of the automatictransmission to the drive position. This allows the driver to drive thevehicle. In this drive condition, the transmission controllerautomatically switches the transmission in accordance with the vehiclespeed and the throttle angle, or throttle position.

To park the vehicle, the driver shifts the shift lever to switch thetransmission to the park position from the drive position or from thereverse position. This locks the output shaft of the transmission toprevent the vehicle from moving by itself accidentally.

However, when the driver wants to drive the vehicle forward from aparked state, the driver might operate the shift lever erroneously, withthe result that the transmission is shifted to the reverse position fromthe park position, which causes the vehicle to move backward. Also, adriver might drive the vehicle forward by mistake when the driverintends to drive backward from the parked state.

To temporarily stop the engine, or to idle the engine, the shift leveris switched to the neutral position or to the park position from thedrive position when the vehicle is stopped. Then, the ignition switch isturned off. To drive the vehicle again, the engine is re-started byturning the ignition switch while depressing the brake pedal. Then, theshift lever is switched to the drive position from the neutral positionor from the park position, and the accelerator is pressed. That is,idling the engine requires shifting the shift lever.

Also, there is a case where the driver may leave the vehicle with theengine running, the parking brake applied, and the shift lever in thedrive position. However, in such a condition, the vehicle mightaccidentally move by itself if the idle speed is increased by anautomatic control procedure.

Additionally, if a collision occurs and an air bag is actuated, thedriver would not be able to continue driving the vehicle, and thevehicle would stop with the transmission in the drive position. Thismight cause the vehicle to move by itself accidentally.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide avehicle transmission controller that automatically switches atransmission to a proper engagement position in accordance with thestate of the vehicle.

To achieve the above object, the present invention provides a vehicletransmission controller that controls switching of the gear position ofa transmission. The controller includes a manipulator that ismanipulated to select a gear position of the transmission. Thecontroller further includes an actuator that actuates the transmissionto switch the gear position in accordance with a manipulation of themanipulator. The actuator switches the transmission to the gear positionselected by the manipulator. Also, the actuator switches thetransmission to a predetermined gear position from the gear positionselected by the manipulator when the vehicle satisfies predeterminedconditions.

Other aspects and advantages of the invention will become apparent fromthe following description, taken in conjunction with the accompanyingdrawings, illustrating by way of example the principles of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, together with objects and advantages thereof, may best beunderstood by reference to the following description of the presentlypreferred embodiments together with the accompanying drawings in which:

FIG. 1 is a diagrammatic view showing a vehicle transmission controlleraccording to a first embodiment of the present invention;

FIG. 2 is a perspective view showing a shift device and a shift positionindicator;

FIG. 3(a) is a front view showing a shift gate of the shift device;

FIG. 3(b) is a front view showing the shift position indicator;

FIG. 4(a) is a diagram showing positions of the transmission when ashift lever is switched from a park position;

FIG. 4(b) is a diagram showing positions of the transmission when theshift lever is switched from a neutral position;

FIG. 4(c) is a diagram showing positions of the transmission when theshift lever is switched from a drive position;

FIG. 4(d) is a diagram showing positions of the transmission when theshift lever is switched from the reverse position;

FIG. 4(e) is a diagram showing positions of the transmission when theshift lever is switched from a drive position in a manual transmissionmode;

FIG. 5 is a flowchart showing a routine of automatic switching controlaccording to a first embodiment of the present invention;

FIG. 6 is a flowchart showing another routine of the automatic switchingcontrol according to the first embodiment of the present invention;

FIG. 7 is a flowchart showing another routine of the automatic switchingcontrol according to the first embodiment of the present invention;

FIG. 8 is a flowchart showing another routine of the automatic switchingcontrol according to the first embodiment;

FIG. 9 is a flowchart showing a routine of automatic switching controlaccording to a second embodiment of the present embodiment;

FIG. 10 is a flowchart showing another routine of the automaticswitching control according to the second embodiment of the presentinvention;

FIG. 11 is a flowchart showing a routine of automatic switching controlaccording to a third embodiment of the present invention; and

FIG. 12 is a flowchart showing another routine of automatic switchingcontrol according to the third embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An automatic transmission controller according to a first embodiment ofthe present invention will now be described with reference to FIGS. 1through 8.

As shown in FIG. 1, the vehicle transmission controller 10 includes anelectronic transmission control unit (hereinafter referred to asSBW-ECU) 11, a shift device 12, a shift position indicator 13, ahydraulic transmission actuator 14, and a gear position detector 15.

As shown in FIG. 2, the shift device 12 is integrated with a steeringcolumn S. The shift device 12 includes a cross-shaped shift gate 12 aand a momentary switch. The momentary switch has a shift lever 16, or amanipulator, which is located at the intersection of the cross. From theoriginal position S0 at the intersection of the cross, the shift lever16 is manipulated in four directions, upward, downward, leftward, andrightward. Specifically, the shift device 12 can be shifted from theoriginal position S0 to a first position S1 in the direction of adriver, to a second position S2 in a direction away from the driver, toa third position S3 in a downward direction, and to a fourth position S4in an upward direction. The shift device 12 detects that the shift lever16 has been shifted from the original position S0 to one of thepositions S1 to S4. The shift device 12 then outputs a signalcorresponding to the result of the detection to the SBW-ECU 11.

As shown in FIG. 1, an automatic transmission includes the hydraulictransmission actuator 14. The transmission also includes a plurality ofelectromagnetic control valves (not shown), which work in response toelectric signals. A gear train of the transmission 17 is switched by theelectronic control valves that control supply and discharge of actuationoil supplied from a hydraulic pump. The transmission is switched betweena neutral position N, a park position P, a drive position D, and areverse position R.

Additionally, in the drive position D, the transmission can be switchedbetween four different gear ratios.

The gear position detector 15 is accommodated in a housing of the geartrain. The detector 15 detects whether the transmission is in the parkposition P, the neutral position N, the drive position D, or the reverseposition R, and which one of the ratios has been selected when thetransmission is in the drive position D. The detector 15 then suppliesthe SBW-ECU 11 with a signal corresponding to the result of thedetection.

The SBW-ECU 11 includes a microcomputer (not shown). The microcomputerexecutes a pre-stored control program. The SBW-ECU 11 controls thehydraulic actuator 14 and thus switches the transmission. The control ofthe hydraulic actuator 14 is executed based on a detection signal fromthe shift device 12 and a detection signal from the gear positiondetector 15.

Specifically, referring to FIG. 4(a), when the transmission is in thepark position P, the SBW-ECU 11 holds the transmission in the parkposition P if the shift lever 16 is shifted from the original positionS0 to the first position S1. The SBW-ECU 11 switches the transmission tothe neutral position N from the park position P if the shift lever isshifted from the original position S0 to the second position S2. TheSBW-ECU 11 switches the transmission to the reverse position R from thepark position P if the shift lever is shifted from the original positionS0 to the third position S3. In the same manner, the SBW-ECU 11 switchesthe transmission to the drive position D from the park position P if theshift lever 16 is shifted from the original position S0 to the fourthposition S4. The drive position D permits an automatic drive mode, whereone of the different gear ratios is automatically selected. In theautomatic drive mode, an electronic controller (hereinafter referred toas ECT-ECU) 18, which is connected to the SBW-ECU 11, controls theswitching of the transmission based on the vehicle speed and thethrottle angle, or throttle position, under a well-known controlprocedure. The SBW-ECU 11 includes a brake interlocking function, whichperforms switching from the park position P to one of the otherpositions only when a brake signal has been supplied from a main brakeswitch 22 (discussed later).

Referring to FIG. 4(b), when the transmission is in a neutral positionN, the SBW-ECU 11 holds the transmission in the neutral position N ifthe shift lever 16 is shifted from the original position S0 to thesecond position S2. The SBW-ECU 11 switches the transmission to the parkposition P from the neutral position N if the shift lever 16 is shiftedfrom the original position S0 to the first position S1. Likewise, theSBW-ECU 11 switches the transmission to the reverse position R from theneutral position N if the shift lever 16 is shifted from the originalposition S0 to the third position S3. In the same manner, the SBW-ECU 11switches the transmission to the drive position D from the neutralposition N if the shift lever 16 is shifted from the original positionS0 to the fourth position S4.

As shown in FIG. 4(c), when the transmission is in a drive position D,the SBW-ECU 11 holds the transmission in the drive position D if theshift lever 16 is shifted from the original position S0 to the fourthposition S4. The SBW-ECU 11 switches the transmission to the neutralposition N from the drive position D if the shift lever is shifted fromthe original position S0 to the second position S2 or to the thirdposition S3. The SBW-ECU 11 switches the transmission from the driveposition D to a drive position M, or a manual switch mode, if the shiftlever 16 is shifted from the original position S0 to the first positionS1.

Referring to FIG. 4(d), when the transmission is in the reverse positionR, the SBW-ECU 11 holds the transmission in the reverse position R ifthe shift lever 16 is shifted from the original position S0 to thereverse position R3. If the shift lever is shifted from the originalposition S0 to the first position S1, the SBW-ECU 11 switches thetransmission from the reverse position R to the park position P. If theshift lever is shifted from the original position S0 to the secondposition S2 or to the fourth position S4, the SEW-ECU 11 switches thetransmission from the reverse position R to the neutral position N.

Referring to FIG. 4(e), when the transmission is in the manual switchmode (the drive position M), the SBW-ECU 11 switches the transmission toa position where the next higher gear ratio is provided if the shiftlever is shifted from the original position S0 to the third position S3.In the same manner, the SBW-ECU 11 switches the transmission to aposition where the preceding lower gear ratio is provided if the shiftlever 16 is shifted from the original position S0 Lo the fourth positionS4. If the shift lever 16 is shifted from the original position S0 tothe first position S1, the SBW-ECU 11 holds the transmission in thedrive position M. If the shift lever 16 is shifted from the originalposition S0 to the second position S2, the transmission is switched tothe drive position D, or the automatic drive mode.

The instant a signal commanding an automatic transmission mode is inputfrom the SBW-ECU 11, the ECT-ECU 18 controls a hydraulic unit based on avehicle speed and a throttle angle. Further, the ECT-ECU 18 performs awell-known automatic transmission control procedure in which thetransmission is successively switched between the four different gearratios. On the other hand, unless the signal commanding the automatictransmission mode is supplied from the SBW-ECU 11, the ECT-ECU 18 doesnot control the hydraulic unit.

The shift position indicator 13, as shown in FIG. 3(b), includes a parkposition display 13 a for indicating that the transmission is in thepark position P, a neutral position display 13 b for indicating that thetransmission is in the neutral position N, a reverse position display 13c for indicating that the transmission is in the reverse position R, anda drive position display 13 d for indicating that the transmission is inthe drive position D. The shift position indicator 13 also includes amanual mode display 13 e for indicating that the transmission is in themanual transmission mode. The indicator 13 further includes a geardisplay 13 f for indicating one of the numbers, 1 to 4, which representa gear selected from the four gears available in the manual transmissionmode.

The shift indicator 13 controls the displays 13 a to 13 f in accordancewith a control signal output from the SBW-ECU 11. The park positiondisplay 13 a lights up when the SBW-ECU 11 holds the transmission in thepark position P. The neutral position display 13 b lights up when theSBW-ECU 11 holds the transmission in the neutral position N. Likewise,the reverse position display 13 c lights up when the transmission isheld in the reverse position R, and the drive position display 13 dlights up when the transmission is held in the drive position D in theautomatic transmission mode. Further, the manual mode display 13 elights up when the transmission is in the drive position M in the manualtransmission mode. The gear display 13 f lights up so that one of thenumbers 1 to 4, which corresponds to a selected gear position, appearson the display 13 f.

Referring to FIG. 1, an input interface circuit of the SBW-ECU 11 isconnected to an engine switch 20, an accelerator switch 21, a pedalbrake switch 22, an accelerator depression sensor 23, a parking brakeswitch 24, an engine speed sensor 25, and a vehicle speed sensor 26.Further, the input interface circuit is connected to a door switch 27, aseated passenger detection switch 28, an air bag sensor 29, and anemergency radio switch 30 or emergency radio device. A radar ECU 31 isalso connected to the input interface circuit. The SBW-ECU 11 detectsvehicle conditions based on signals supplied from the switches 20, 21,22, 27, 28, 30, signals supplied from the sensors 23, 15, 26, 29, and asignal from the ECU 31.

The engine switch 20 is a momentary switch for starting or stopping theengine regardless of the operation of the ignition switch. The engineswitch 20 is electrically connected to an engine electronic controller(hereinafter referred to as an EG-ECU) 32. An engine starter 33 iselectrically connected to the EG-ECU 32. Well-known controls, such ascontrol of fuel injection based on the engine speed and control of theignition timing based on the intake air amount and the crank position,are performed by the EG-ECU 32. If the engine switch 20 is turned onwhen the engine is at a standstill, the EG-ECU 32 controls the enginestarter 33 to start the engine. At this time, even if the engine switch20 is kept on after the engine starts, the EG-ECU 32 controls the enginestarter 33 such that the starter 33 is not affected by the running ofthe engine. Once the engine switch 20 is turned on, the EG-ECU 32 turnsoff the switch 20. On the other hand, if the engine switch 20 is turnedon again when the engine is running, the EG-ECU 32 stops the engineregardless of the length of time during which the engine switch 20remains on.

An accelerator switch 21 outputs a signal, which represents depressionamount of an accelerator (not shown). The pedal brake switch 22 outputsa signal, which represents depression amount of a pedal brake (notshown). The depression sensor 23 detects the force applied to theaccelerator pedal and outputs a signal corresponding to the result ofthe detection. The parking brake switch 24 outputs a parking brakesignal when the parking brake (not shown) is moved. The engine speedsensor 25 detects tho engine speed and outputs an engine speed signal.The vehicle sensor 26 detects the vehicle speed and outputs a vehiclespeed signal.

The door switch 27 outputs a signal indicating that the door (not shown)adjacent to the driver's seat (not shown) is open. The seated passengerdetection switch 28 outputs a detection signal upon detecting that adriver is seated on the driver's seat. The air bag sensor 29 outputs asignal upon detecting a vehicle collision in which the air bag (notshown) is actuated. An emergency radio unit 34 is electrically connectedto the emergency radio switch 30. If the emergency radio switch 30 isturned on, radio signals are output to the SBW-ECU 11 and the emergencyradio unit 34. When the switch 30 is turned on, the emergency radio unit34 transmits a signal to a predetermined base transceiver station (notshown).

A monitor radar 35, or collision warning device, is electricallyconnected to a radar ECU 31. The monitor radar 35 monitors in thedirection behind the vehicle and outputs a warning signal to the SBW-ECU11 when another vehicle is closely approaching from behind.

The vehicle transmission controller 10 according to the presentembodiment includes the SBW-ECU 11, the shift device 12, the shiftposition indicator 13, the hydraulic transmission actuator 14, the gearposition detector 15, the engine switch 20, the accelerator switch 21,the pedal brake switch 22, the depression sensor 23, the parking brakeswitch 24, the engine speed sensor 25, the vehicle speed sensor 26, thedoor switch 27, the seated passenger detection switch 28, the air bagsensor 29, the emergency radio switch 30, the radar ECU 31, theemergency radio unit 34, and the monitor radar 35.

The SBW-ECU 11 executes the automatic switching control, whichautomatically switches the transmission according to the drive conditionof the vehicle thereby assisting a driver in the shifting operation. Theautomatic switching control will now be discussed with reference toFIGS. 5 to 8.

The flowchart in FIG. 5 shows a routine of the automatic switchingcontrol. When a vehicle speed is zero in step S10, the flow proceeds tostep 11. If the engine is running in step S11, the flow proceeds to stepS12. The SBW-ECU 11 determines in step S12 whether or not thetransmission is in the park position P or the neutral position N. If thetransmission is in the park position P or the neutral position N, theSBW-ECU 11 determines in step S13 whether the pedal brake has beenapplied or not. If it is determined in step S13 that the pedal brake hasbeen applied, the flow proceeds to step S14. If the accelerator has beendepressed in step 14, the flow proceeds to step S15. In step S15, theSBW-ECU 11 controls the hydraulic transmission actuator 14 to switch thetransmission to the drive position D in the automatic transmission modefrom the park position P or from the neutral position N.

Specifically, the SBW-ECU 11 determines that the transmission can beswitched to the drive position D since the vehicle is at a standstill,the brake is applied, the engine is running, and the transmission is inthe drive position P or the neutral position N. In the drive conditions,the SBW-ECU 11 determines that the driver, when depressing theaccelerator while the pedal brake is applied, intends to switch thetransmission to the drive position D. In this way, the ECU 11automatically switches the transmission to the drive position D from thepark position P or from the neutral position N thereby assisting thedriver in the shifting operation.

Even if the accelerator has not been depressed in step S14, the SBW-ECU11 switches the transmission from the park position P or from theneutral position N to the drive position D when the parking brake isreleased in step S16. Specifically, the ECU 11 determines that, when thedriver releases the parking brake while keeping the engine running andkeeping the pedal brake applied, the driver intends to switch thetransmission to the drive position D.

When the pedal brake has not been applied in step S13, the SBW-ECU 11holds the transmission in the park position P or in the neutral positionN and allows the engine to idle.

The flowchart in FIG. 6 shows another routine of the automatic switchingcontrol. When the vehicle speed is zero in step S20 and the engine isrunning in step S21, the SBW-ECU 11 determines in step S22 whether ornot the transmission is in the park position P or the neutral positionN. When the transmission is in the park position P or the neutralposition N in step S22, the flow proceeds to step 23. If the pedal brakehas been applied in step S23, the flow proceeds to step S24. If theaccelerator has not been applied in step 24, the flow proceeds to step25. If it is determined in step S25 that the parking brake has beenreleased twice in succession, the SBW-ECU 11 switches the transmissionto the reverse position R from the park position P or from the neutralposition N in step S26.

Specifically, when the vehicle is at a standstill, the engine isrunning, and the transmission is in the park position P or the neutralposition N, the SBW-ECU 11 determines that, when the driver releases theparking brake twice in succession while keeping the pedal brake applied,the driver intends to switch the transmission to the reverse position R.In such a drive condition, the ECU 11 automatically switches thetransmission from the park position P or from the neutral position N tothe reverse position R thereby assisting the driver in shifting thetransmission.

A flowchart in FIG. 7 shows another routine of the automatic switchingcontrol. When the vehicle speed is zero in step S30 and the engine isnot running in step S31, the SBW-ECU 11 determines in step S32 whetheror not the transmission is in the park position P or the neutralposition N. If the transmission is in the park position P or the neutralposition N in step S32 and the pedal brake has been applied in step S33,the flow proceeds to step S34. If the engine switch 20 has been actuatedlonger than a predetermined time in step S34 and the engine is runningin step S35, the ECU 11 switches the transmission to the drive positionD (the automatic transmission mode) from the park potion P or from theneutral position N in step S36. When the engine starts while the engineswitch 20 is on, the engine starter 33 is not influenced by the runningof the engine.

Specifically, when the vehicle is at a standstill, the engine is notrunning, and the transmission 17 is in the park position P or theneutral position N, the SBW-ECU 11 determines that, when the engineswitch 20 has been actuated longer than the predetermined time while thebrake pedal has been depressed, the driver intends to switch thetransmission to the drive position D. In this drive condition, the ECU11 automatically switches the transmission to the drive position D fromthe park position P or from the neutral position N, thus assisting thedriver in the shifting operation.

If, in the process of step S34, the length of time that the engineswitch 20 is kept on is shorter than the predetermined time, the EG-ECU32 performs an ordinary engine start procedure.

A flowchart in FIG. 8 shows another routine of the automatic switchingcontrol. When a vehicle speed is zero in step S40 and the engine isrunning in step S41, the SBW-ECU 11 determines in step S42 whether ornot the transmission is in the drive position D or the reverse positionR. When the transmission is in the drive position D or the reverseposition R in stop S42, the flow proceeds to step S43. If the pedalbrake has been applied in step S43, the routine further proceeds to stepS44. If the engine switch 20 remains actuated longer than thepredetermined time in step S44, it is determined in step S45 whether theengine is running or not. If the engine is not running in step S45, theECU 11 switches the transmission to the park position P from the driveposition D or from the reverse position R in step 46.

Specifically, when the vehicle is at a standstill, the engine isrunning, and the transmission is in the drive position D or the reverseposition R, the SBW-ECU 11 determines that, when the driver operates theengine switch 20 longer than the predetermined time while keeping thebrake pedal depressed, the driver intends to switch the transmission tothe parking position P. In this drive condition, the ECU 11automatically switches the transmission to the park position P from thedrive position D or from the reverse position R to assist the driver inthe shifting operation.

On the other hand, if the length of time that the engine switch 20remains on is shorter than the predetermined time at step S44, the flowproceeds to step S47. If the parking brake has been applied in step S47,the transmission is switched to the park position P from the driveposition D at step S46. That is, when the vehicle is at a standstill,the engine is running, and the transmission is in the driving position Dor the reverse position R, the ECU 11 determines that, when the driverapplies the parking brake while keeping the brake pedal depressed, thedriver intends to switch the transmission to the park position P.

If the parking brake has not been applied in step S47, the EG-ECU 32performs an ordinary engine stop procedure.

The vehicle transmission controller according to the present embodimenthas the following advantages.

According to the present embodiment, if the vehicle is at a standstill,the engine is running, and the transmission 17 is in the park position Por the neutral position N, the transmission is automatically switched tothe drive position D the instant the driver depresses the acceleratorwhile maintaining application of the pedal brake or the instant thedriver releases the parking brake while maintaining application of thepedal brake.

This make it unnecessary for the driver to perform a shifting operationwhen moving the vehicle from a standstill. Accordingly, the driver canstart the car quickly. Further, this eliminates the possibility, whichexists with manual shifting, that the driver might switch thetransmission to the reverse position R by mistake when the driverintends to select the drive position D.

When the vehicle is at a standstill, the engine is running, and thetransmission is in the park position P or the neutral position N, thetransmission is automatically switched to the reverse position R if thedriver applies the pedal brake and releases the parking brake twice insuccession without depressing the accelerator pedal.

This makes it unnecessary for the driver to perform a shifting operationwhen moving the vehicle backwards from a standstill. Accordingly, thedriver can move the car backward quickly. Further, this prevents thepossibility, which exists with manual shifting, that the driver mightswitch the transmission to the drive position D by mistake when thedriver intends to select the reverse position R.

If the vehicle is at a standstill, the engine is not running, and thetransmission is in the park position P or the neutral position N, thetransmission of the transmission 17 is automatically switched to thedrive position D when the engine switch 20 is actuated longer than thepredetermined time while the pedal brake is maintained in an appliedstate.

This makes it unnecessary for the driver perform a shifting operationwhen moving the vehicle from a standstill. Accordingly, the driver canstart the car quickly. Further, this prevents the possibility, whichexists with manual, shifting, that the driver might switch thetransmission to the reverse position R by mistake when the driverintends to select the drive position D.

If the vehicle is at a standstill, the engine is running, and thetransmission is in the drive position D or the reverse position R, thetransmission is automatically switched to the park position P when thedriver operates the engine switch 20 longer than the predetermined timewhile keeping the pedal brake applied, and the engine consequentlystops.

This makes it unnecessary for the driver to perform a shifting operationwhen parking the vehicle. Therefore, the driver can park the vehicleeasily.

A second embodiment of the present invention will now be described withreference to FIGS. 9 and 10. The second embodiment is substantially thesame as the first embodiment shown in FIGS. 1 to 8, except that theSBW-ECU 11 executes automatic parking control. Therefore, to avoidredundancy, like or same reference numerals are given to thosecomponents that are like or the same as the corresponding components ofthe first embodiment.

The automatic parking control will now be described with reference toFIG. 9.

The flowchart in FIG. 9 shows the routine of the automatic parkingcontrol. When the vehicle speed is zero in step S50, the SBW-ECU 11determines in step S51 whether the transmission is in the park positionP or not. If it is determined that the transmission is not in the parkposition P in step 51, the flow proceeds to step S52. If the dooradjacent to the driver's seat is open in step S52, the flow proceeds tostep S53. When it is determined that in step S53 that the driver is notseated, the SBW-ECU 11 switches the transmission to the park position Pfrom the drive position D, from the reverse position R, or from theneutral position N in step S54.

Specifically, if the vehicle is at a standstill and the transmission isnot in the park position P but in the drive position D, the reverseposition R, or the neutral position N, the SBW-ECU 11 determines thatthe vehicle might accidentally run by itself. From the information thatthe door is open and the driver is not seated, the ECU 11 furtherdetermines that the vehicle must be prevented from moving by itself. Insuch a condition, the SBW-ECU 11 automatically switches the transmissionto the park position P from the drive position D, from the reverseposition R, or from the neutral position N, thus preventing the vehiclefrom accidentally moving by itself.

The flowchart in FIG. 10 shows another routine of the automatic parkingcontrol. When the vehicle speed is zero in step S60, the SBW-ECU 11,determines in step S61 whether the transmission is in the park positionP or not. If the transmission is not in the park position P in step S61,the flow proceeds to step S62. If it is determined in step S62 that thevehicle has been in a collision in which the air bag was actuated, theECU 11 switches the transmission to the park position P from the driveposition D, from the reverse position R, or from the neutral position Nin step S63.

Specifically, if the vehicle is stopped and the transmission is in aposition other than the park position P, the SBW-ECU 11 determines thatthe vehicle might accidentally run by itself from the stopped state.From the determination that the vehicle has been involved in acollision, the ECU 11 also determines that the driver cannot perform ashift operation due to injury by the collision and that the vehicle mustbe stopped from running by itself. In such a condition, the ECU 11automatically shifts the transmission to the park position P from thedrive position D, from the reverse position R, or from the neutralposition N, thus preventing the vehicle from moving by itself from thehalted state.

If, in step S62, the SBW-ECU 11 does not detect a collision in which theair bag has been actuated, the flow proceeds to step S64. If theemergency radio switch 30 is on in step S64, the ECU 11 switches thetransmission to the park position P from the drive position D, from thereverse position R, or from the neutral position N in step S63. That is,from the information that the emergency radio switch 30 is on when thetransmission is in any position other than the park position P when thevehicle is stopped, the ECU 11 determines that the driver may beincapable of shifting. Accordingly, the ECU 11 prevents the vehicle fromrunning by itself.

Also, if the emergency radio switch 30 is not on at step S64, the flowproceeds to step S65. If, at step S65, a radar ECU 31 provides acollision warning as a result of monitoring performed by the monitorradar 35, that is, when the distance between the vehicle and anothervehicle is smaller than a predetermined value, the flow proceeds to stepS63.

Specifically, when the vehicle is stopped, the transmission is in aposition other than the park position, and it is determined that anothervehicle might collide with the vehicle, the SBW-ECU 11 switches thetransmission to the park position. Therefore, even if the anothervehicle collides with the vehicle, the movement of the vehicle resultingfrom the collision is restricted to prevent another collision.

The vehicle transmission controller according to the present embodimenthas, in addition to the advantages of the first embodiment, thefollowing advantages.

In the present embodiment, when the vehicle is stopped and thetransmission is not in the park position P, the transmission isautomatically switched to the park position P if the door adjacent tothe driver's seat is open and the presence of the driver is not detectedin the driver's seat. Therefore, even if the driver forgets to shift thetransmission to the park position P, the transmission is automaticallyswitched to the park position P. This prevents the vehicle from runningby itself due to an increase in the idle speed, a sloping road, or anexternal force exerted by strong wind or impact of another vehicle. If achild or a pet moves or touches the shift lever 16, a brake interlockprevents the transmission from being switched from the park position Pto the drive position D, to the reverse position R, or to the neutralposition N. Accordingly, the vehicle is securely prevented from runningby itself.

When the vehicle is stopped and the transmission is not in the parkposition P, the transmission is automatically switched to the parkposition P if the air bag is actuated by a collision, if the emergencyradio switch 30 is turned on, or if there is a possibility that thevehicle might be hit by other car.

This prevents the vehicle from running by itself if the driver isinjured by collision and therefore cannot perform the shiftingoperation. This also prevents the vehicle from running by itself if, forsome reason, the driver cannot continue driving. Further, this preventsthe vehicle from moving in the event of collision, thus avoiding anotheraccident.

A third embodiment of the present invention will now be described withreference to FIGS. 11 and 12. The third embodiment is substantially thesame as the first embodiment shown in FIGS. 1 to 8, except that theSBW-ECU 11 executes automatic neutral control. Therefore, to avoidredundancy, like or same reference numerals are given to thosecomponents that are the same as the corresponding components of thefirst embodiment.

The flowchart in FIG. 11 shows the routine of the automatic neutralcontrol. When the vehicle speed is not zero at step S70 and when thetransmission is in the drive position D or the in the reverse position Rat step S71, the flow proceeds to step S72. When it is determined instep S72 that the degree of accelerator depression exceeds apredetermined amount, the SBW-ECU 11 switches the transmission to theneutral position N from the drive position D or from the reverseposition R at step S73. The predetermined accelerator depression amountis an amount of force exerted suddenly on the pedal.

Specifically, when the vehicle is running and the transmission is in thedrive position D or in the reverse position R, the SBW-ECU 11 determinesthat the driver might erroneously step on the accelerator instead of thebrake. From the vehicle information that the accelerator pedal has beendepressed with a force exceeding the predetermined depression amount,the ECU 11 determines that the vehicle speed might suddenly increase ifthe driver accidentally depresses the accelerator pedal instead of thepedal brake. In drive condition, the ECU 11 automatically switches thetransmission to the neutral position N from the drive position D or fromthe reverse position R to prevent the vehicle from running in anunexpected manner.

The flowchart in FIG. 12 shows another routine of the automatic neutralcontrol. When the vehicle speed is greater than a predetermined speed atstep S80 and the engine speed is lower than a predetermined speed atstep S81, the flow proceeds to step S82 to determine whether thetransmission is in the drive position D or the reverse position R. Whenthe transmission is in the drive position D or the reverse position R atstep S82, the ECU 11 automatically switches the transmission to theneutral position N from the drive position D or from the reverseposition R.

Specifically, when the vehicle is running at a speed that exceeds apredetermined vehicle speed, the SBW-ECU 11 determines that the vehiclemay not be driven as the driver expects. From such information, the ECU11 determines that the fuel is running out and that this may cause anabnormal decrease in the engine speed and a sudden drop in the vehiclespeed. In this condition, the EUC 11 automatically switches thetransmission to the neutral position N from the drive position D or fromthe reverse position R to prevent a sudden drop in the vehicle speed.

The above discussed vehicle transmission controller according to thethird embodiment has, in addition to the advantages of the first andsecond embodiments, the following advantages.

In the procedure of FIG. 11, if the accelerator pedal is depressed withan amount of force that is greater than a normal amount, thetransmission is automatically switched to the neutral position N fromthe drive position D or from the reverse position R.

This prevents the power of the engine from being transmitted to thedrive wheels even if the driver depresses the accelerator with a forcegreater than the predetermined amount. This prevents the vehicle speedfrom suddenly increasing to an extremely high speed and causing anaccident,

In the procedure of FIG. 12, if the engine speed drops below apredetermined engine speed when the vehicle is running at a speedexceeding a predetermined vehicle speed, the transmission isautomatically switched to the neutral position N. This prevents theengine brakes from being applied suddenly when the fuel runs out duringthe running of the vehicle. Accordingly, the vehicle runs by inertiawithout decreasing the vehicle speed suddenly. This enables the driverto check a meter to learn that the vehicle lacks fuel. Therefore, thedriver can drive the vehicle to the shoulder of the road by inertia tostop the vehicle.

A driver who has not experienced a lack of fuel might not switch thetransmission to the neutral position N upon a sudden decrease of thevehicle speed. Instead, the driver might try to re-start the engine withthe transmission in the drive position D or in the reverse position R.In the present embodiment, such situation is avoided since thetransmission is automatically switched to the neutral position N. Also,an excessive load is not applied to the transmission of the transmission17 since excessive reverse torque is not applied to the transmission bythe engine when the fuel is used up.

The above described embodiments are to be considered illustrative andnot restrictive, and the present invention may be embodied in thefollowing forms.

In the second embodiment in FIGS. 9 and 10, information that the dooradjacent to the driver's seat is open and that the door was locked fromoutside could also be used for the automatic parking control. In such asituation, the transmission is automatically switched to the parkposition P even if the driver forgets to shift the transmission to thepark position P when parking the vehicle. In a vehicle in which a dooris remotely controlled by a radio switch or optical communication, thereis no need to provide another seated passenger detection switch 28.

The automatic parking control according to the second embodiment may useinformation telling an engine start permitting means has detected theabsence of the driver from the driver's seat. The engine startpermitting means permits the driver to start the engine when verifyingthe driver's identification code registered in the vehicle.

The automatic parking control according to the second embodiment can useinformation that an air bag controller (air bag control means) hasdetected the absence of the driver. The air bag controller detects thepresence of the driver by a pressure sensor, a dielectric sensor, or anultrasonic sensor and permits the actuation of the air bag when sensinga predetermined seated state.

The automatic parking control can use information that a sleeping driverdetector (sleeping driver detecting means) has detected that the driveris dozing at the wheel.

The illustrated embodiments use an automatic transmission 17 thatswitches the gear ratio stepwise by changing the gear combination of thetransmission when in the drive position D. However, a CVT (non-stepwisetransmission) that changes a gear ratio continuously could also be used.

The illustrated embodiments use the automatic transmission. However, anelectrically-controlled transmission that manually switches a gear ratioin accordance with the operation of the shift device could also be used.

The SBW-ECU 11 may switch the shift lever of the shift device 12 to acorresponding shift position by an electric actuator.

The engine switch 20 may be a rotary switch like conventional ignitionkey switches, which include an on-position, an off-position, and astart-position.

Therefore, the present examples and embodiments are to be considered asillustrative and not restrictive and the invention is not to be limitedto the details given herein but may be modified within the scope andequivalence of the appended claims.

What is claimed is:
 1. A vehicle transmission controller that controlsswitching of the gear position of a transmission, the vehicle includingan accelerator and a pedal brake, which brakes the vehicle when a brakepedal is depressed, the controller comprising: a manipulator that ismanipulated to select a gear position of the transmission; and anactuator that actuates the transmission to switch the gear position inaccordance with a manipulation of the manipulator, wherein the actuatorswitches the transmission to the gear position selected by themanipulator, and wherein, when the vehicle is stopped, an engine of thevehicle is running, and the transmission is in a park position or aneutral position, the actuator switches the transmission to a driveposition if the accelerator pedal is pressed while the brake pedal isdepressed.
 2. A vehicle transmission controller that controls switchingof the gear position of a transmission, the vehicle including anaccelerator and a pedal brake, which brakes the vehicle when a brakepedal is depressed, the controller comprising: a manipulator that ismanipulated to select a gear position of the transmission; and anactuator that actuates the transmission to switch the gear position inaccordance with a manipulation of the manipulator, wherein the actuatorswitches the transmission to the gear position selected by themanipulator, wherein, when the vehicle is stopped, an engine of thevehicle is running, and the transmission is in a park position or aneutral position, the actuator switches the transmission to the driveposition if the parking brake is released while the brake pedal isdepressed.
 3. A vehicle transmission controller that controls switchingof the gear position of a transmission, the vehicle includes an engineswitch, which is turned on or off to start or stop the engine, a pedalbrake, which brakes the vehicle, and a parking brake, the controllercomprising: a manipulator that is manipulated to select a gear positionof the transmission; and an actuator that actuates the transmission toswitch the gear position in accordance with a manipulation of themanipulator, wherein the actuator switches the transmission to the gearposition selected by the manipulator, and wherein, when the vehicle isstopped, an engine of the vehicle is running, and the transmission is ina park position or a neutral position, the actuator switches thetransmission to a drive position if the engine switch is turned on whilethe brake pedal is depressed.
 4. A vehicle transmission controller thatcontrols switching of the gear position of a transmission, the vehicleincluding an engine switch, which is turned on or off to start or stopthe engine, and a pedal brake, which brakes the vehicle, the controllercomprising: a manipulator that is manipulated to select a gear positionof the transmission; and an actuator that actuates the transmission toswitch the gear position in accordance with a manipulation of themanipulator, wherein the actuator switches the transmission to the gearposition selected by the manipulator, and wherein, when the vehicle isstopped, an engine of the vehicle is running, and the transmission is ina park drive position or a reverse position, the actuator switches thetransmission to a park position if the engine switch is turned on whilethe brake pedal is depressed.
 5. A vehicle transmission controller thatcontrols switching of the gear position of a transmission, the vehicleincluding an engine switch, which is turned on or off to start or stopthe engine, a pedal brake, which brakes the vehicle, and a parkingbrake, the controller comprising: a manipulator that is manipulated toselect a gear position of the transmission; and an actuator thatactuates the transmission to switch the gear position in accordance witha manipulation of the manipulator, wherein the actuator switches thetransmission to the gear position selected by the manipulator, andwherein, when the vehicle is stopped, an engine of the vehicle isrunning, and the transmission is in a park drive position or a reverseposition, the actuator switches the transmission to a park position ifthe parking brake is applied while the brake pedal is depressed.
 6. Avehicle transmission controller that controls switching of the gearposition of a transmission, the vehicle including an air bag and acollision sensor, which detects a collision in which the air bag isactuated, the controller comprising: a manipulator that is manipulatedto select a gear position of the transmission; and actuator thatactuates the transmission to switch the gear position in accordance witha manipulation of the manipulator, wherein the actuator switches thetransmission to the gear position selected by the manipulator, andwherein the actuator switches the transmission to the park position whenthe transmission is in a drive position, a reverse position, or aneutral position and when the collision sensor detects such a collision.7. A vehicle transmission controller that controls switching of the gearposition of a transmission, the vehicle including an emergency radiodevice, which transmits an emergency signal by radio transmission, thecontroller comprising: a manipulator that is manipulated to select agear position of the transmission; and an actuator that actuates thetransmission to switch the gear position in accordance with amanipulation of the manipulator, wherein the actuator switches thetransmission to the gear position selected by the manipulator, andwherein the actuator switches the transmission to the park position whenthe transmission is in a drive position, a reverse position, or aneutral position and an emergency signal is transmitted from theemergency radio device.
 8. A vehicle transmission controller thatcontrols switching of the gear position of a transmission, the vehicleincluding a collision warning device, which warns that another vehiclemay collide with the vehicle when the distance between the vehicle andthe other vehicle becomes smaller than a predetermined value, thecontroller comprising: a manipulator that is manipulated to select agear position of the transmission; and an actuator that actuates thetransmission to switch the gear position in accordance with amanipulation of the manipulator, wherein the actuator switches thetransmission to the gear position selected by the manipulator, andwherein the actuator switches the transmission to the park position whenthe transmission is in a drive position, a reverse position, or aneutral position and when the collision warning device is providing acollision warning.
 9. A vehicle transmission controller that controlsswitching of the gear position of a transmission, the vehicle includingan accelerator and an accelerator depression sensor, which detects adepressing force applied to the accelerator, the controller comprising:a manipulator that is manipulated to select a gear position of thetransmission; and an actuator that actuates the transmission to switchthe gear position in accordance with a manipulation of the manipulator,wherein the actuator switches the transmission to the gear positionselected by the manipulator, and wherein the actuator switches thetransmission to a neutral position when the vehicle is not stopped, thetransmission is in a drive position or a reverse position, and thedepression sensor detects that the accelerator is being depressed with aforce greater than a predetermined value.